The menu at the top of this page provides links to documents and data from the Understanding America Study's American Life in Realtime (ALiR) Study.
The goal of ALiR is to use activity trackers to understand how day-to-day activity and sleep behaviors relate to physical and mental health in a representative sample of Americans.
This study began in August of 2021 with a nationally representative sample of 1,038 UAS members who were provided with Fitbit inspire 2 devices and were followed over the course of one year. Since then, we have allowed members to continue to contribute Fitbit data for as long as they wish to participate. In addition, we have continued to add additional participants and devices (e.g., Apple Watch).
To date, we have collected over XX days of continuous activity tracker data across YY unique participants. Currently there are XX active members, though this is expected to grow to over 10,000 over the next few years.
ALiR’s documentation and datafiles are currently available for research use by inquiry. Please contact ALiR study director, Dr. Ritika Chaturvedi @ ritikac@usc.edu.
Data will be available for download through the data pages in Spring of 2025. Data elements include (Table 1):
- Baseline surveys.
- Monthly repeated surveys.
- Fitbit’s provided daily data summaries (general Use Tier): activity, steps, sleep, heart rate (HR), heart rate variability (HRV), SpO2, temperature, basal metabolic rate (BMR).
- Derived data summaries by UAS’s inhouse analytics team (general use tier): walking speed, gait, circadian rhythm, device wear patterns.
- Fitbit’s raw intraday (minute level) data (restricted tier): activity, steps, sleep, HR, HRV, SpO2, temperature, BMR.
